The third era features 3 passenger trains named after ancient gods and heroes - one of which is a bonus engine.
You can unlock engines by spending research points generated by the Laboratory in your Train Station. Once the required pre-requisites are met, you can develop the next engine. A coupling system is available at the end of each era, allowing engines to transport goods from the next era.
Note: You don’t need to research anything from Era 1 or 2 to start researching Era 3 engines.
Ajax
Requirements
Research the Dionysos cargo engine
Research all of its level I upgrades
Research Cost: 35 Research Points
Slots: 1 | Reliability: 80% | Acceleration: 14/20 | Speed: 175 km/h | Passengers: 55
Artemis
Requirements
Research the Prometheus cargo engine
Research all of its level I upgrades
Research Cost: 40 Research Points
Note: Artemis is a multi-slot engine and takes up two (2) slots instead of one (1)
Slots: 2 | Reliability: 40% | Acceleration: 3/20 | Speed: 80 km/h | Passengers: 200
Electra (Bonus)
The Electra is the Passenger Bonus Engine of Era 3.
It can be bought in the Rail Nation Shop or won through the Lottery or competitions in Era 4.
Note: The price decreases if purchased in a later era.
Slots: 0 | Reliability: 95% | Acceleration: 20/20 | Speed: 190 km/h | Passengers: 75